Due to the advantages of high speed,low delay and high confidentiality,underwater wireless optical communication(UWOC)has become a potential application of underwater wireless communication. In this paper, the models and research status of UWOC systems are briefly summarized,and the key technologies used in the UWOC system,including the selection of light source,modulation coding,detection,channel modeling and other key technologies,are emphatically described,and a design scheme of UWOC system is introduced. Finally,aiming at the problems of realizing underwater long-range communication and high-speed transmission,the future development trend and challenges of UWOC are summarized,which provides a reference for the future development direction and practicality of UWOC.